Actuator Fault-Tolerant Control for an Electro-Hydraulic Actuator Using Time Delay Estimation and Feedback Linearization

Abstract

This article proposes a novel fault-tolerant controller for a double-rod electro-hydraulic actuator whilst the motion control system faces with system disturbances/uncertainties and internal leakage fault. Firstly, taking the advantage of the coordinate transformation, the nonlinear system is converted to a linear system to apply the control design tools in linear control theory. Besides, the matched, mismatched disturbances, and internal leakage fault are integrated into a new lumped uncertainty based on this transformation. Inspired by the great capability of time delay estimation technique, the suggested controller is developed to effectively detect and compensate for the internal leakage fault. To enhance the performance of the control system, an adaptive integral sliding mode control approach is deployed to effectively suppress the lump estimated error, and the effects of fault. The perfect combination of inputoutput feedback linearization, adaptive integral sliding mode, and time delay estimation is investigated to achieve high-precision tracking control and strong robustness in the presence of matched, mismatched disturbances, and faults, simultaneously. Moreover, the global stability of the suggested control algorithm is demonstrated by the Lyapunov theory. Finally, several tracking performance comparisons of the proposed approach with the existing controllers to demonstrate the efficiency are exhibited through simulation analyses and experiment results.

Fault-tolerant control for an electro-hydraulic servo system with sensor fault compensation and disturbance rejection

“…Remark 1 Note of the Assumption 1a, c: These are common assumptions that has been conducted in literature, for instance [1,4,12] to facilitate verifying the system stability. Note of the Assumption 1b is necessary to satisfy the conditions during the designing process of the presented NUIO.…”

“…Hence, the unknown input vector u has been decoupled. The state estimation error dynamics (12) simplify to…”

“…The core idea of this approach is to create an observer to approximate the different disturbances in the system and then mitigate their effect through a control design procedure. Various disturbance observers were induced, such as adaptive disturbance observer [10], high-gain disturbance observer [11], time delay estimation [12], ESO [13][14][15], and so on. Typically, the well-known ESO exhibited the online estimation of the lumped disturbances, and only one parameter needs to be regulated without too much system information.…”

Suspension System Control Based on Type‐2 Fuzzy Sliding Mode Technique

“…Moreover, due to stability proof being asymptotical, the sliding phase does not exist, and chattering is eliminated. In [30], linearization of hydraulic actuator equation is used rstly.…”

Extended sliding mode observer‐based high‐accuracy motion control for uncertain electro‐hydraulic systems

“…Hence, as one of the most popular control problems for such EHSSs, the position tracking control has been currently receiving a vast amount of attention in recent years. By virtue of model compensation mechanisms, nonlinear control techniques such as feedback linearization control, 7,8 sliding mode control (SMC), 9,10 and back-stepping control (BC) 11,12 are powerful tools to synthesize controllers for highly nonlinear EHSSs. However, the controllers constructed based on the aforementioned control techniques cannot achieve a high-accuracy position tracking performance for EHSSs subject to uncertainties and disturbances arising from parameter deviations, modeling errors, unknown external loads, and so on, since these terms are not fully taken into consideration in the control mechanisms.…”